A beloved sea otter that underwent a landmark surgery at the Vancouver Aquarium on Monday has died.

Corky was rescued in Tofino in mid-August after a suspected boat strike, and was found suffering blunt force trauma, a fractured rib and other injuries.

Unable to dive or forage for food on his own in the wild, he was taken to the Vancouver Aquarium Marine Mammal Rescue Centre, where staff learned one of his kidneys had ruptured.

That’s when the bloated marine mammal was given the name Corky, because of the way he was found bobbing around the surface of the water near Vargas Island.

It turned out the otter had gas trapped in his thorax, which moved underneath his skin to cause a condition known as subcutaneous emphysema.

Veterinary experts from Seattle were brought in to perform a kidney removal and transfusion on Corky, in what’s believed to be the first surgery of its kind on a sea otter. The blood donor for the transfusion was Elfin, one of the four otter residents of the aquarium.

But despite “heroic” efforts by the international surgical team, Corky died while in recovery Wednesday morning.

Emily Johnson, the centre’s manager, said in a statement Corky’s case was an inspiring rescue effort.

“The surgery was nothing short of amazing, and I thought he just might pull through. He seemed to have that much will,” she said.

“He was a special little guy.”

Although his condition was critical and the odds were stacked against him, Dr. Martin Haulena says the effort was well worth it.

“We learned so much from him,” he said in a statement.

“His treatment contributes to a greater body of vet knowledge which will help us with future rescue efforts.”